The subject application is related to subject matter disclosed in Japanese Patent Application No. 2000-233493 filed on Aug. 1, 2000 in Japan to which the subject application claims priority under Paris Convention and which is incorporated herein by reference.
1. Field of the Invention
This invention relates to a cleaning processing method and a cleaning processing apparatus for processing objects-to-be-processed, e.g. semiconductor wafers, glass substrates for LCD""s, etc., with chemical liquids and cleaning liquids.
2. Related Background Art
In cleaning processing methods and cleaning processing systems, this kind, objects-to-be-processed, such as glass substrates for LCD""s, semiconductor wafers, etc. (hereinafter referred to as xe2x80x9cwafersxe2x80x9d), are processed for cleaning off the contaminants staying thereon with processing liquids containing various kinds of chemical liquids and rinsing liquids (cleaning liquids).
The contaminants on the surfaces of wafers include, for example, particles, metals, organic matters, oxide films, etc. Chemical liquids vary depending on kinds of the contaminants, and include a mixed liquid of ammonium hydroxide diluted with pure water and hydro-peroxide (NH4OH/H2O2/H2O), a mixed liquid of dilute hydrochloric acid diluted with pure water and hydro-peroxide (HCl/H2O2/H2O), hydro-fluoric acid diluted with pure water (HF/H2O), etc. Also, the rinsing liquids are used mainly to rinse off the chemical liquids staying on the wafers and include pure water, ozone water, etc.
Then, the wafers are immersed one after another into processing tanks containing the chemical liquids etc. to have the contaminants removed and rinsed with the chemical liquids. However, the wafers successively conveyed to the cleaning processing system vary in the kind of the contaminants. Therefore, it is necessary to install a plurality of processing tanks respectively containing different chemical liquids so that each wafer could be immersed into a designated processing tank.
However, in the conventional cleaning processing method and cleaning processing system, there is a disadvantage that, while a preceding wafer is being processed with a chemical liquid in a certain processing tank, the following wafer, requiring the processing with the same chemical liquid must wait until the cleaning of the preceding wafer, being firstly processed, is completed. Under the situation, it results in lack of cleaning efficiency.
The present invention has been made in view of the above-described situation, and an object of the present invention is to provide a cleaning processing method and a cleaning processing apparatus that can improve cleaning processing efficiency.
In order to achieve the above-described object, the cleaning processing method according to the present invention is characterized by:
installing a plurality of processing units for processing at least one object-to-be-processed with a plurality of kinds of processing liquids, and enabling the same kind of a processing liquid to be supplied to at least two processing units of the plurality of the processing units;
upon making processing by successively introducing objects-to-be-processed each of which has its own processing sequence into a plurality of processing units, choosing one or more of the processing units into which an object to be firstly processed is carried, by checking a processing sequence of an object to be processed afterwards so as to shorten a whole processing time of the objects-to-be-processed being judged.
Also, the cleaning processing apparatus according to the present invention comprises:
a plurality of processing units for processing an object-to-be-processed with a plurality of kinds of processing liquids, the same kind of a processing liquid being capable of being supplied to at least two of the plurality of processing units;
a controller for, upon successively introducing objects-to-be-processed each having its own processing sequence into a plurality of processing units, checking the processing sequence of the object to be processed afterwards to choose one or more of the plurality of the processing units into which an object to be firstly processed is carried so that a whole processing time of the objects-to-be-processed being judged can be shortened.
According to the present invention structured as described above, the first processing unit which can provide a processing liquid A and the third processing unit which can provide the processing liquid A and a processing liquid B can be installed for example, since a plurality of kinds of processing liquids can be provided for each processing unit and the same kind of processing liquid can be provided for at least two processing units. Consequently, in a case of consecutively conveying two objects-to-be-processed of a processing sequences to be processed with the processing liquid A, the object to be firstly processed can be processed by the first processing unit, and the object to be processed afterwards can be successively processed by the third processing unit. That is to say, there is no wasting time by staying in the line even in a case of consecutively processing two objects-to-be-processed of the same processing sequence.
Likewise, by setting the same processing liquid for three or more processing units, even if three or more objects-to-be-processed of the same processing sequence are consecutively conveyed, those objects-to-be-processed can be successively processed. However, even when the same processing liquid is set in two processing units, a time during which the third object-to-be-processed stays in the line can be shortened enough since the processing of the first object-to-be-processed would have been far progressed by the time the third object-to-be-processed is to be processed. Accordingly, cleaning efficiency of objects-to-be-processed can be improved.
Moreover, according to the present invention, when making processing by successively loading objects-to-be-processed into a plurality of processing units wherein each of the object-to-be-processed requires its own processing sequence, a processing unit is chosen for the object-to-be-processed which is to be firstly processed to be conveyed into by checking the processing sequence of the object-to-be-processed which is to be processed afterwards so as to shorten the whole processing time of the objects-to-be-processed. According to the present invention, a processing unit for an object-to-be-processed to be firstly processed in can be chosen in consideration of processing sequences of objects to be processed afterwards so as to shorten a whole processing time of the objects-to-be-processed being judged (two or more groups of objects-to-be-processed to be decided for their processing units); in other words, economic conditions, complicated handling, simplicity of processing, etc. are considered, and under those conditions, a processing unit for an object to be firstly processed can be chosen to make a whole processing time as short as possible.